Use the 2 point formula:
No, it does not as long as it follows the rule.
Say you subbed with 7
Then the numerator must be from the same point you subbed first, in this case, it has to be -4.
Regardless which way you put which points in first, you will always get the same answer.
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To refrain from getting confused, label the points.
and
and
or
and
and